the nitrogen is part of the cooling system and he wasnt getting reception, he was playing an offline game, the genetically altered spiders gave him a fast healing time, the lizards were summoned by connor's expirements, and connors killed his boss

I was also thinking he should've just extracted the kid from the car with the biocable, but considering he was holding onto the car itself with one hand and his own suspension biocable with the other, it would've been a pretty difficult move. I'd assume he would jerk up the car for a sec and then aim the web-shooter at the kid (like he eventually did anyway once the bumper gave way). When he has to traverse that great distance to get to Oscorp before the climatic battle, he misses that huge crane on the first go. Maybe he just lacked confidence in his web-shooter aim during the bridge incident.